A microfiche appendix is attached to the present specification and forms a part of the present application. This microfiche appendix is entitled DBMS, and consists of a total number of 6 microfiche and a total number of 534 frames.
The present invention relates to a system and method for the storage, manipulation and retrieval of data according to relational concepts to support real-time acquisition of control and management data from processes being monitored and distribution of that data on an event-driven basis.
The invention particularly relates to a database management system (DBMS) of the relational type which is to be employed for controlling ongoing industrial processes.
Known database management systems, constructed primarily for the processing of business data, can be accessed at a speed which permits the retrieval of data elements at a rate of several elements per second. The updating of such a database can require several seconds to complete. A primary reason for these speed limitations is that the primary database storage medium is a nonvolatile storage medium, typically a disk. This is an attractive storage medium because it permits the storage of a large quantity of data inexpensively and compactly.
However, such database systems are not capable of operating at the speeds required by many industrial processes, and particularly processes involving a large number of values which must be monitored and control values which must be derived and transmitted to appropriate controllers. For many industrial processes of this type, the rate at which data values must be read and updated in the database can be of the order of several hundred events per second.